The potato leafhopper, (Empoasca fabae) a true bug related to treehoppers, cicadas, and spittlebugs, feeds on a variety of plant species and has been reported to feed on nearly 200 kinds of plants. Vegetables attacked by this insect include beans, eggplant, lettuce, peanut, potato,
soybean, squash, and sweet potato.
Adult potato leafhoppers are usually yellowish or pale green. They exhibit much color variation, often leading to misidentification. The head of the adult often has pale or dark-green spots and six or more pale spots on the back immediately behind the head. These insects are active, jumping or flying when disturbed, and can run as quickly sideways or backwards as they can forward.
Adults have wings while nymphs do not. The wings are held rooflike over the abdomen. Adults are about 3.5 millimeters (mm) long and wedge-shaped, tapering to the rear.
Infested plants may exhibit a condition known as “hopperburn.” The combination of heavy feeding and toxin from the saliva causes tissues of the leaf to become yellow and chlorotic. Affected leaves may roll and curl inward and eventually the leaf tissue becomes brown and necrotic.
Survival And Spread
The potato leafhopper is a common vegetable pest in Florida as it over-winters in the state and the Gulf States and migrates north in the spring. The eggs are white to pale white, slender, elongated, and about 0.9 mm long. Adults live about one month, but have been recorded as living as long as 120 days. Females mate within two days after their final molt and begin laying eggs about six days afterwards. An entire life cycle can be completed in about four weeks, and as many as six generations may occur each year.
Nymphs are similar in shape to the adults but are smaller and lack wings. There are five nymphal instars. They are so small they usually remain unnoticed until plants start showing the effects of feeding damage.
Feeding and egg laying cause damage including curling, stunting, and dwarfing of infested plants. Larger nymphs cause most of the damage. Nymphs and adult leafhoppers feed by puncturing the undersides of leaves and suck the sap out with their piercing mouthparts. The injection of saliva into the phloem during feeding by potato leafhoppers may cause disease-like symptoms. Unlike other leafhoppers, the potato leafhopper is not known to transmit viruses and others diseases.
No cultural practices have proven effective in controlling this pest. Varietal resistance does seem to occur in some crops but has not been substantiated yet. Infestation in a greenhouse can be reduced by adequate screening of window and open areas, as well as proper sealing of door edges. A variety of chemical insecticides, including the neonicotinoids, pyrethroids, and growth regulators like Courier (buprofezin, Nichino America) will provide adequate control depending on the crop. Organic producers can employ soaps and oils as well as Entrust (spinosad, Dow AgroSciences) and various neem formulations. Be sure to read the label and check for OMRI listing.
By Gene McAvoy, Regional Vegetable Extension Agent IV, University of Florida, IFAS.